There are a few points I want to make clear before we move the discussion to the nature of linearity and emergence. The first point is most games do not feature linear gameplay on the micro level. Outside of a few genres (rhythm-action, puzzle, point-click style adventure games) most video games feature very emergent micro level gameplay. Though I presented examples of games on a scale of linearity, the truth is non-linear gameplay is not easy to measure. By definition linearity and non-linearity are two sides of a coin; they're binary. Gamplay is either linear or non-linear. So when I described some games as being "fairly linear" I did so according to a cursory analysis. Explicitly measuring non-linearity is a task that I may tackle later in a separate article series.
As evident in the many examples I presented, games can achieve non-linear gameplay on many levels and in a variety of ways. Though most people conflate emergent, non-linear gameplay with dynamic, open, rich, multi-choice gameplay linear gameplay can feature many of these associated qualities as well.
Linear gameplay can be very complex or very simple. This is to say that there can be many rules to the game or few. Moment to moment, linear gameplay can give the player many options to choose from or as few as one option. No matter the kind of game, it's easy to imagine creating a level or a mode where the player can only win through a single sequence of actions. Linear games can also be unpredictable or different every time we play, a quality commonly attributed to emergent games. For example, imagine a game that generates a random challenge where players have to press a fixed sequence of buttons without error. You don't have to imagine it. You can play our game here: KNOWLEDGE by B.E.S.
As unintuitive as it may seem, linear gameplay can be dynamic as long as the linear challenge is altered by a non-player controlled factor. The reason the dynamic factor can't be player controlled is because that would create a branch in potential game states (because the player would have the option to activate the dynamic factor or not). With two potential player influenced gamestates one state must make the challenge easier than the other (or the difference would be too inconsequential to matter in the first place). When the challenge is lessened in this way, there will invariably be multiple sequences of actions players can take to achieve victory. To keep the gameplay linear, the gameplay influencing actions must never branch and allow players to achieve victory using more than one sequence of actions. For a simple example, imagine if KNOWEDGE had a line of code in it that made blue and green notes more likely to occur in the randomize sequences at night. This design would make the time of day a dynamic element that influences the linear sequences.
Linearity is not a positive or a negative feature or an indicator of quality. Some of the most simple, linear games I've played have made it onto my GOTY lists. And some very complex, non-linear games have been the my most disappointing (Knights in the Nightmare, Xenoblade, Final Fantasy 13, etc). Well tuned, rushed, and unpolished games alike can be linear or non-linear. Linear gameplay can be very obtuse with very cryptic solutions that are only found via blind trial-and-error (The Viridian Room, Super Karoshi, The Hitchhikers Guide To the Galaxy). And non-linear gameplay can be just as obtuse with lacking tutorials, guiding features, or a gameplay focus.
It's possible to have the illusion of openness in very linear games. The Uncharted 3 desert scene, parts of Journey, and many others games appear to let the player explore large, open areas. Yet there's nothing significant to do except stumble across the "right way" to progress. Other times you'll run up against invisible walls and other clear limitations making it very apparent that the world is not as open as it appeared. On the other hand, it's possible to have an illusion of linearity in very non-linear or open games. After all sequence breaking in games like Metroid or Herocore is about taking events out of order of the "main path" or skipping them altogether. Figuring out how to break sequences is regarded as a puzzle or a secret in itself, which is why it's not obvious. Though well known now, the warp pipes in Super Mario Brothers are a great example of a seemingly linear campaign that becomes non-linear upon discovering the secrets. Some Zelda bosses that appear to require a straight forward sequence of actions to defeat allow the player to use various tools for additional solutions (e.g. Puppet Ganon). The Ghost Train in Final Fantasy 6 is a great example of a boss with a clever alternate solution.
The result of our investigation so far is that the topic of linearity vs non-linearity is not very interesting. When we're merely concerned with whether or not a sequence of challenges can be done in at least 2 different orders, such a analysis falls somewhat flat. As I tried to indicate, simply being linear or non-linear doesn't say a lot about a game, what genre it is, how fun or challenging the gameplay is, how many player options there are, how well crafted it is, etc. Part of me hardly cares about the freedom to do things in different orders. If I have 5 boring chores to do, whether I clean the kitchen first or start wtih the bathroom, I still have 5 chores to do. If these chores are not fun, rearranging them hardly matters. I love gameplay, period. Whether gameplay is in a fixed sequence or I can shuffle things around doesn't matter to me much. I'm looking for interesting experiences and fun challenges. There are so many other interesting details and design topics to consider that get to the heart of a game design analysis, that it's hardly worth dwelling on the topic of linearity alone.
To get to the heart of the issue, we have to understand linearity and emergence on a very fundamental level. Having defined and demystified linear and emergent gameplay we can now dive deeper into the nature of both.
The Nature of Linearity
Linearity has a nature, meaning that there are specific limitations and qualities inherent in linear works that come about simply because of the fixed, sequential way such works must be experienced. Each medium has developed craft techniques and rules to work around or with these limitations instead of fighting against it. Because the vast majority of music, books, and films are linear works we can draw some insight into the nature of linearity from these mediums.
image by Meredeth Nemirov
Even writing a single paragraph, the limitations of the linear presentation of information are apparent. When I write, I generally start with a thesis or topic sentence. From there I flesh out the details. And even when I write about a step by step process there are times when I want to introduce another idea or topic into the discussion. It's like playing a song and wanting to throw in a new melody; for example if I played the Super Mario Bros theme on piano I might throw in a bit of Rainbow Road from Mario Kart. Returning to the original topic you realize that there has been a diversion in the flow of ideas; a jump almost. You realize that in a linear medium, presenting different ideas or exploring different concepts will always create more of these kinks in the flow because there's no direct, sequential, linear way to move between two unrelated topics.
The previous paragraph simultaneously explains and illustrates a limitation of the linear presentation of ideas. For another illustration, imagine traveling on branches in a tree. You can only move so far along one branch. And when you decide to explore another branch you'll ultimately have to jump from branch to branch or do a little backtracking. Put another way, in a fixed linear progression of different subjects, concepts, or ideas you'll either present jumps in subjects or inefficiently present redundant information.
To lessen the jarring impact of these conceptual jumps or kinks in the flow, artists of all kinds use simple reminders. Like the first sentence of this paragraph or the paragraph above it, by restating the topic I can be very clear about how far back you should think before I branch off on another topic. Writers also, just for illustration (not that you needed another explanatory-illustrative example), use dependent clauses, parenthesis, brackets, margin comments, and foot notes to insert and organize branching information. Working around linear limitations isn't just about reminding the audience, but about tracing conceptual paths to create a sort of map. And this mental map making is an art unto itself that I'll investigate in articles to come. For now, I'll give one more example. Music heavily uses repetition to keep listeners on track like in this Chopin etude. With music especially, the repetition and precise changes to the material create ever widening waves and patterns that work to more clearly convey information; see TED talk here. It's no coincidence that the speaker in the video talks about musical phrases, grammar, language, and chunking all in one talk.
Linearity has a nature, and a power, and a way unto itself that I can tap into to communicate better. But if you're thinking that the lessons learned from the nature of linearity doesn't apply to non-linear video games, consider this. There is an inherent linearity in all learning. One way to think about this is that though we engage in activities with a full range of sensory perception, we still organize and process concepts fairly linearly, a few bits at at a time. This is most likely due to the strong connection thinking, logic, and language have with each other in our minds. Through internalized private speech and grammar rules we've learned to think by forming sentences in our mind. And because we think using linear language, our learning process is linear as well. And because acquiring the skills for skill-based gameplay is a learning experience, the nature of linearity applies to both linear and non-linear gameplay experiences.
There's something about the way a fixed sequence of information allows me to relax and go with the flow. Being "locked in for the ride" has a certain clarity and focus that is hard to find otherwise. And for a creator or a communicator, having so much control over what my audience will perceive or experience and in what order is extremely powerful. Like an elementary school teacher it's easier to do your job when you have a good idea of where the eyes and minds of your students are focused. For if you let a classroom of students do their own thing, or even do what you ask in any order they want, chaos will surely follow.
In part 5, we'll look at the nature of emergence.